Hot takes:
Implying that only females can direct this movie is implying females aren't good enough to compete with male directors. They are good enough, but the fact that no men can compete for the role of director says otherwise.
Yes, Captain Marvel is supposed to be a bastion of female empowerment, but disqualifying male directors is misandry, which is not feminism and not okay.
A textbook example of feminism would be allowing both women and men to compete for the spot, not favoring women or favoring men, but favoring talent, because talent is non-discriminatory.
If someone were to say that only a cishet male could direct Thor, there would be outrage. This post is not the polar opposite of that, rather, a different side to the same coin.
TLDR: Pick talent, not gender. That's textbook definition sexism.